Power shutdowns intended to prevent more devastating California wildfires are raising new concerns about another longstanding environmental threat: air pollution.
As utilities halted service to more than 2 million people this week, lines formed at hardware stores selling portable generators, while many hospitals and businesses fired up their own. The prospect of emissions belching from untold numbers of the machines, some powered by diesel and gasoline as well as propane and natural gas, was troubling in a state already burdened with some of the nation's worst air quality.
"It is a major concern," said Dr. Laki Tisopulos, executive officer of the Ventura County Air Pollution Control District. "Imagine if you are in a large metropolitan area like Los Angeles or the (San Francisco) Bay Area and you have hundreds or thousands of these engines kicking in. All of a sudden you have many localized sources of pollution that are spewing carcinogens right where we breathe. It can be next door to a school, a hospital."
Questions also arose over how the blackouts might affect traffic patterns, potentially causing even more tie-ups and discharges than usual from vehicles. They are a leading factor in California air pollution, along with a warm, sunny climate that helps produce ozone and topographical features such as the Central Valley where polluted air often stagnates.